Underfeed stoker



Dec, 16,

N. M. LOWER UNDERFEED S'IOKER Filed Dec. 1920 4 Sheets-Sheet 2 Dec. 16,1 4- 1,519,382 N. M. LOWER Y UNDERFEED STOKER Filed Dec. 11, 1920 4Sheets-Sheet 5 Dec. 1924. 1,519,382

N.. M. LOWER UNDERFEED STOKER Filed Dec. 11, 1920 4 Sheets-Sheet 4lfiyentor: jJf/hvz law a citizen of the United States, and residenttoand which- Patented Dec. 16, 1924.

UNITED STATES PATENT OFFICE.

NATHAN M. LOWER, OF PITTSBURGH, PENNSYLVANIA, ASSIGNO'R TO LOCOMOTIVESTOKEB COMPANY, A CORPORATION OF PENNSYLVANIA.

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Application filed December 11, 1920. Serial No. 429,968.

To all whom it may concern: being formed in sections, as 19, 20, whichBe it known that I, NATHAN M. LOWER, are located between the channels14, 15.

7 Fuel is delivered to the channel 13 from of Pittsburgh, county ofAllegheny, and a conduit 21 entering through its bottom State ofPennsylvania, have invented cerand adjacent the front endof thefire-box, tain new and useful Improvements in Unthere being a conveyingscrew 22 within the derfeed Stokers, of which the following is a conduit21 for advancing the fuel. Fuel is specification, and which-areillustrated in delivered into the conduit 21 from any suittheaccompanying drawings, forming a part able source, not shown. In thecase of a thereof. locomotive fuel would be taken from the The inventionrelates to underfeed stokers tender, and inasmuch as the deviceisillusprimarily intended for use in connection trated as adapted for useon a locomotive with locomotives but readily adapted to the conduit 21is shown as being sectional stationary furnaces. I in form, the twosections being united by The objects of the invention are to proa balland socket joint, as 23, to permit vide improved means for feeding thefuel of relative movement of the two vehicles.

spreading it upon the grate surface, As the fuel enters the channel 13 aportion and to acilitate the coking of the fuel.

The invention consists in a structure such of lateral channels, theremainder being caras that hereinafter described and as illusriedforward by the screw section 19, wheretrated in the. accompanyingdrawings, in upon a portion of it enters the next pair of lateralchannels, and eventually all of Fig. 1 is a detail plan section of afurnace these lateral channels are su plied. v taken above its grate,some of the detailsof The bottom of the firex is inclined constructionbeing in part omitted; downwardly from the central channel, and Fig. 2is a detail central longitudinal consequently the fuel entering thelateral vertical section through the fire-box; channels will be advancedtherein in part Fig. 3 is a detail, partly in section, of a by gravity.Tilting advancing plates, as

rear elevation of the furnace,- on line 3-3 24, are located in thebottoms of these several of Fig. 2; lateral channels, such plates ateach side Fig. 4 is a detail section on the line of the fire-box beingcarried upon a single 4.-4 of Fig. 1, some parts being omitted; rockershaft 25, by means of which they are Fig. 5 is a detail section on theline 55 swun upwardly and laterally, thereby pushof F 1g. 4; and ingorward the fuel which rests upon or Fig. 6 is a sectional detail of aratchet do, has passed them. In order to prevent fuel vice used in theoperating mechanism. from dropping tlfrough the apertures in the Thefire-box of a locomotive is indicated. bottoms of the channels, withinwhich these at 10, its back head 11 being provided with plates arefitted, each plate is provided at the usual hand firing opening 12. Theits swinging end and sides with a depending bottom of the fire-box isprovided with a skirt 26. central longitudinal channel 13, from whichThe pressure exerted upon the fuel by the there lead laterally towardeach side wall screw 22 and the screw sections, as 19 and of thefire-box channels, as 14,. 15, their 20, forces the fuel into thelateral channels number being dependent upon the len h in such quantityas to cause it to overflow of the fire-box. The portions of the reuponthe grate surfaces 16, and the advancbox. bottom, intermediate of thelateral ohaning ressure exerted by the plates 24 has a nels 14, 15, aregrated, as represented at 16, simi ar effect The lateral channels serveand upon them the combustion of the fuel the additional function ofcoking retorts, is mainly accomplished. The side walls of so that whenthe fuel reaches the grate surthe channels 14, 15, may be and preferablfaces its volatile content has been largely are provided with a seriesof air oms}; eva orated. The combustion commences ad'acent their uppermargins. within the channels, due to the air entering lthin the channel13. there is located a through the ports 17, and is completed 11 onshaft 18, car ing a conveying screw or the grated surfaces. Any ashwhich oes spiral vane which 1s preferably interrupted, not escapethrough the grates gravitates to of it will find its way into the firstpair I retained by the valve 28 a su cient time to cause its completecombustion, air ports 29 being provided in one wall of the passage 27.above the valve.

The shaft 18 is. rotated from a prime mover, conventionally shown at 30,the means provided for transmitting power -from this motor to the shaftbeing shown as ,wheel 48, driving the chain 31 thro a sprocket chain 31.The motor is preferably of the oscillating type,'and power istransmitted from its shaft 47 to the sprockelt ratchet and pawlmechanism 49, shown in Fig. 6.

The shafts, as 32, carrying the ash-dis-.

charging valves are rotated by a step by step movement by means of aratchet wheel 33, mounted upon each, with which there cooperates a pawl34, given an oscillating movement through the medium of a link bar 35,connected with a rocker arm 36 having a slot 37, within which works awrist pin 38 carried by the sprocket wheel 39 on the shaft 18. The twolinks 35, one for each valve, are

adjustably secured to the rocker arm 36, thereby providing forvariations in the throw of the pawls 34, and consequently of the rate atwhich the valves are turned. The shafts 25 are rocked by any suitablemeans, there being conventionally shown for this purpose as connected toeach through one of the cranks 42 and a connecting-rod a reciprocatingmotor 40, rocking a shaft 41, which is connected to the shaft 25 b meansof cranks 42 mounted on the sha 41, and connected by means of links withcrank arms 42 mounted on the shaft 25.

The screw 22 -may be driven from any suitable source of power,preferably derived from the prime mover 30. To this end thereis shown ashaft 43, connected to the prime mover by means of ratchet and pawlmechanism housed within a casing 45, and which may be controlled in anywell known manner, as by means of a lever 46. The shaft 43 may besuitably connected with the rearward end of the screw 22. This drivingmechanism is common in locomotive stokers, and forming no part of thepresent invention is not fully illustrated.

While I have shown an operative structure, the invention may be embodiedin different forms and I do not, therefore, desire to be limited to thedetails as herein shown and described.

I claim as my invention- 1'. In an underfeed stoking device, in combination, a fire-box bottom inclined downward from its middle portiontoward each side thereof and having a central longitudinal the centralchannel, the portions of such bottom intermediate of the lateralchannels being grated meansfor advancing fuel in the central 0 annel,and means for advancing fuel in the lateral channels.

3. In a stoking device, in combination, a firebox bottom inclineddownward from its central portion toward each side thereof and beingprovided with a central longitudinal channel, lateral channels leadingoutwardly from the central channel, the bottoms of the lateral channelsinclining downward from the central channels, and having ash-dischargeopening at the outer ends of said lateral channels, the portions of thebottom intermediate of the lateral channels being grated, and means foradvancing fuel through the central channel and causing its dischargeinto the lateral channels.

4. In an underfeed stoking device, in combination, a fire-box bottominclined downward from its middle portion toward each side thereof andhaving a central longitudinal channel and lateral channels leadingoutwardly therefrom, the bottoms of the lateral channels incliningdownward from the central channel, the portions of such bottomintermediate of the lateral; channels being grated, and a screw conveyorwithin the central channel.

5. In an underfeed stoking device, in combination, a fire-box bottominclined downward from its middle portion toward each side thereof andhaving a central longitudinal channel and lateral channels leadmgoutwardl therefrom, the bottoms of the lateral c annels. incliningdownward from the central channel, the portions of such bottomintermediate of the lateral channels being grated, and a shaft withinthe central channel having an interrupted screw vane.

6. In a stoking device, in combination, a fire-box bottom inclineddownward from its central portion toward each side thereof and beinprovided with a central longitudinal c annel, lateral channels leadinoutwardly from the central channel an having ash-discharge openings atthe outer ends of said, lateral channels, the bottoms of the lateralchannels inclining downward nausea the lateral channels incliningdownward from the central channel, the portions of such bottomintermediate of the lateral channels being grated and the side walls ofthe lateral channels having air ports, and means for advancing fuel inthe central channel. 1

8. In an underfeed stoker, in combination, a fire-box bottom having acentral longitudinal channel and lateral channels leading therefrom, thebottoms of the lateral channels inclining downward from the centralchannel, and means for forcing fuel throu h the central channel.

9. 11 an underfeed stoker, in'combination, a fire-box bottom having acentral longitudinal channel and lateral channels leading therefrom, thebottoms of the lateral channels inclining downward from the centralchannel, the portions of the bottom between the lateral channels beinggrated, and means for forcing fuel through the central channel.

10. In an underfeed stoker, in combination, a fire-box bottom havin acentral longitudinal channel and latera channels leading therefrom, thebottoms of the lateral channels inclining downward from the centralchannel, the side walls of the lateral channels being provided with airports, and means for forcmg fuel through the central channel.

11. In an underfeed stoker, in combination, a fire-box bottom having acentral longitudinal channel and lateral channels leading therefrom, thebottoms of the lateral channels inclining downward from the centralchannel, such bottom being provided with ash-discharge openings at itss1de margins, and means for forcing fuel through the central channel.

12. In an underfeed stoker, in combination, a fire-box bottom having acentral lonitudinal channel and lateral channels leadmg therefrom, thebottoms of the lateral channels inclining downward from the centralchannel, such bottom being provided with valve-controlled ash-dischargeopenings at its side mar ins, and means for forcing fuel through t ecentral channel.

13. In an underfeed stoker, in combination, a fire-box bottom having acentral longitudinal channel and lateral channels leading therefrom, thebottoms of the lateral channels inclining downward from the centralchannel, a feed conduit deliverin to the 'rearward end of the centralchanne andv means for forcing fuel through such conduit.

14. In an underfeed stoker, in combination, a fire-box bottom having acentral Ion-- itudinal channel and lateral channels leadmg therefrom,the bottoms of the lateral channels inclinin downward from the centralchannel, a eed conduit delivering to the rearward end of the centralchannel, means for forcing fuel through such conduit, and means foradvancing fuel in the lateral channels. a

15. In an underfeed stoker, in combination, a fire-box bottom having acentral longitudinal channel and lateral channels leading therefrom, thebottoms of the lateral channels inclinin downward from the centralchannel, a eed conduit delivering to the forward end of the centralchannel, means for forcin fuel through such conduit, an oscillata leplate in each lateral channel for advancing fuel therein, and

means for actuating such plates.

16. In an underfeed stoker, in combination, a fire-box bottom having acentral channel and lateral channels leading therefrom, a rotative shaftlocated longitudinally within the central channel, and a series of screwflights mounted on the shaft and between the lateral channels.

17. In an underfeed stoker, in combination, a fire-box bottom having acentral channel extending longitudinally thereof and lateral channels incommunication with said central channel, said lateral channels extendingoutwardly and forwardly from said main channel, and means for forcingfuel along said central channel.

18. In an underfeed stoker, in combina-, tion, a fire-box bottom havinga central channel and lateral channels leading there from, said centralchannel inclined downward from the rear to the front of said fire-box,and means for forcing coal along a said central channel.

NATHAN M. LOWER.

